Thread plug gauge with maintenance line, thread ring gauge, and method of manufacturing the same

ABSTRACT

A thread gauge, which allows to reliably know the time for replacement by visual checking and improves the predetermined dimensional accuracy of a thread product has a go-side thread measuring portion extending from one side of a shank portion coaxially with the shank portion or a not-go-side thread measuring portion extending from an other side of the shank portion coaxially with the shank portion, a wear checking gauge line having a predetermined length and a predetermined depth formed on male thread portions and female thread portions formed on the go-side thread measuring portion or the not-go-side thread measuring portion.

FIELD OF THE INVENTION

The present invention relates to a thread plug with a maintenance lineor the like and thread ring gauge which allow to accurately and reliablyknow the times for replacement of various types of thread gauges andreliably and quickly manufacture thread plug gauges and thread ringgauges by forming, in advance, wear checking gauge lines or round pointson the male and female thread portions of go-side thread measuringportions and not-go-side thread measuring portions forming various typesof thread gauges and letting the gauge lines or round points wear outand disappear due to contact because of repeated insertion and removalbetween the various types of thread gauges and various types of testproducts, and a method of manufacturing the same.

DESCRIPTION OF THE RELATED ART

Conventionally, Utility Model Application Publication No. 62-195704discloses a thread gauge.

The thread gauge disclosed in this patent literature has awear-resistant film formed on the surface of each male thread portion,with the film having a color different from that of each male threadportion. Providing this thread gauge makes it possible to facilitatevisually checking the time for replacement of the thread gauge and toperform precise and economical inspection of female thread products andrepair the thread gauge by regenerating a wear-resistant film.

Utility Model Application Publication No. 55-161201 discloses a ringgauge.

A characteristic feature of this ring gauge is that the thread portionis formed from a refractory metal consisting of 75% to 85% WC and 15% to20% Co. Based on the material characteristics of this refractory metal,this ring gauge exhibits excellent wear resistance because of highhardness, small friction coefficients with respect to objects to bemeasured, and a small coefficient of thermal expansion (about ⅓ that ofa conventional product) because of being the sintered product. Inaddition, for example, the ring gauge exhibits a small temporal changein size because of small residual strain. These make it possible toconsiderably improve the measurement accuracy and tolerance of the ringgauge.

CITATION LIST Patent Literature

-   [Patent Literature 1] Utility Model Application Publication No.    62-195704-   [Patent Literature 2] Utility Model Application Publication No.    55-161201

SUMMARY OF THE INVENTION Problem that the Invention is to Solve

The male thread gauge disclosed in Utility Model Application PublicationNo. 62-195704 described above has a wear-resistant film formed on thesurface of each male thread portion, with the film having a colordifferent from that of each male thread portion, thereby making itpossible to facilitate visually checking the time for replacement of thethread gauge and perform precise and economical inspection of threadproducts. In contrast to this, the present invention allows to reliablyknow the times for replacement of thread gauges by visual check byproviding wear checking gauge lines, each having a predetermined lengthand a predetermined depth, on the male and female thread portions of thethread measuring portions of various types of gauges, without formingany wear-resistant film, and can provide a thread gauge product with ahigher added value than a conventional thread gauge by improving thepredetermined dimensional accuracy of a thread product.

In addition, the present invention can reliably and quickly manufacturethe above thread gauge.

The ring gauge disclosed in Utility Model Application Publication No.55-161201 described above has been improved in measurement accuracy andtolerance by forming the thread portion using a refractory metalconsisting of 75% to 85% WC and 15% to 20% Col. This makes the ringgauge exhibit excellent wear resistance because of high hardness, whichis a material characteristic of a refractory metal, small frictioncoefficients with respect to objects to be measured, and a smallcoefficient of thermal expansion because of being the sintered product.In addition, for example, the ring gauge exhibits a small temporalchange in size because of small residual strain. These make it possibleto considerably improve the measurement accuracy and tolerance of thering gauge.

However, the thread portion of the disclosed ring gauge described abovedoes not allow to easily visually check whether the time for replacementof the ring gauge has come due to wear upon measurement.

In contrast, the present invention allows to reliably know the times forreplacement of thread gauges by visual check by providing wear checkinggauge lines or round points, each having a predetermined length and apredetermined depth, in advance as described above, on the male andfemale thread portions forming the respective thread measuring portions,and letting the gauge line or round point disappear upon repeated gaugemeasurement, and can provide a thread gauge product with a higher addedvalue than a conventional thread gauge by improving the predetermineddimensional accuracy of a thread product.

In addition, the present invention can reliably and quickly manufacturethe thread gauge described above.

Means for Solving the Problem

As a means for solving the problem, the invention defined in claim 1provides a thread plug gauge with a maintenance line or the like inwhich in a thread plug gauge body a having a go-side thread measuringportion 3 extending from one side of a shank portion 1 coaxially withthe shank portion 1 or a not-go-side thread measuring portion 5extending from the other side of the shank portion 1 coaxially with theshank portion 1,

a wear checking gauge line 9 or 14 having a predetermined length and apredetermined depth or a round point having a predetermined depth and apredetermined diameter is formed on a male thread portion 7 or 12 and afemale thread portion 8 or 13 formed on the go-side thread measuringportion 3 or the not-go-side thread measuring portion 5.

As a means for solving the problem, the invention defined in claim 2provides a thread plug gauge with a maintenance line or the like inwhich the wear checking gauge line 9 or 14 formed on the male threadportion 7 or 12 and the female thread portion 8 or 13 of the go-sidethread measuring portion 3 or the not-go-side thread measuring portion 5has a linear shape.

As a means for solving the problem, the invention defined in claim 3provides a thread plug gauge with a maintenance line or the like inwhich the wear checking gauge line 9 or 14 is printed on the male threadportion 7 or 12 and the female thread portion 8 or 13 so as to have adepth of 0.3 μm to 0.4 μm and a width of 0.2 mm.

As a means for solving the problem, the invention defined in claim 4provides a thread plug gauge with a maintenance line or the like inwhich the thread plug gauge with the maintenance line or the like isformed by using alloy tool steel, a ceramic material, or a superhardmaterial.

As a means for solving the problem, the invention defined in claim 5provides a thread plug gauge with a maintenance line or the like inwhich the round point is printed on the male thread portion 7 or 12 andthe female thread portion 8 or 13 so as to have a depth of 0.3 μm to 0.4μm and a diameter of 2 mm.

As a means for solving the problem, the invention defined in claim 6provides a method of manufacturing a thread plug gauge with amaintenance line or the like, comprising connecting a thread plug gaugebody a to a negative electrode base connected to a power supply box bwhich controls a current, setting a green stencil which has a cut-outportion having a desired marking pattern and from which an electrolyticsolution exudes on a carbon filter with the electrolytic solution beingcontained in a positive electrode handle connected to the power supplybox b, energizing the set positive electrode handle while gripping thehandle, and forming a wear checking gauge line 3 on a male threadportion 7 and a female thread portion 8 of a go-side thread measuringportion 3 or a male thread portion 12 and a female thread portion 13 ofa not-go-side thread measuring portion 5 of the thread plug gauge body aby performing a marking process by sliding the positive electrode handleon the male thread portion 7 and the female thread portion 8 of thego-side thread measuring portion 3 or the male thread portion 12 and thefemale thread portion 13 of the not-go-side thread measuring portion 5of the thread plug gauge body a to form a concave shape which has adepth of 0.3 μm to 0.4 μm and a width of 0.2 mm and is blackened.

As a means for solving the problem, the invention defined in claim 7provides a thread ring gauge with a maintenance line or the like inwhich in a thread ring gauge body b or c having an upper surface portion15 and a lower surface portion 16 and having a go-side thread measuringportion 20 formed on an inside portion 17 to have a male thread portion18 and a female thread portion 19 of the same class as that of a screwto be measured or having a not-go-side thread measuring portion 23formed on an inside portion 17 to have a male thread portion 21 and afemale thread portion 22 of the same class as that of a screw to bemeasured,

wear checking gauge lines 24 and 25 each having a predetermined lengthand a predetermined depth or round points each having a predetermineddepth and a predetermined diameter are formed on male thread portions 18and 21 and female thread portions 19 and 22 of the go-side threadmeasuring portion 20 and the not-go-side thread measuring portion 23which are engraved in an inside portion between the upper surfaceportion 15 and the lower surface portion 16 which constitute one of thethread ring gauge bodies b and c.

As a means for solving the problem, the invention defined in claim 8provides a thread ring gauge with a maintenance line or the like inwhich the wear checking gauge line 24 or 25 defined in claim 7 has alinear shape.

As a means for solving the problem, the invention defined in claim 9provides a thread ring gauge with a maintenance line or the like inwhich the wear checking gauge line 24 or 25 defined in claim 7 isprinted on the male thread portion 18 or 21 and the female threadportion 19 or 22 so as to have a depth of 0.3 μm to 0.4 μm and a widthof 0.2 mm.

As a means for solving the problem, the invention defined in claim 10provides a thread ring gauge with a maintenance line or the like inwhich the round point is printed on the male thread portion 18 or 21 andthe female thread portion 19 or 22 so as to have a depth of 0.3 μm to0.4 μm and a diameter of 2 mm.

As a means for solving the problem, the invention defined in claim 11provides a thread ring gauge with a maintenance line or the like inwhich the thread ring gauge body b or c is formed by using alloy toolsteel, a ceramic material, or a superhard material.

As a means for solving the problem, the invention defined in claim 12provides a method of manufacturing a thread plug gauge with amaintenance line or the like, comprising connecting a thread ring gaugebody b or c to a negative electrode base connected to a power supply boxb which controls a current, setting a green stencil which has a cut-outportion having a desired marking pattern and from which an electrolyticsolution exudes on a carbon filter with the electrolytic solution beingcontained in a positive electrode handle connected to the power supplybox b, energizing the set positive electrode handle while gripping thehandle, and forming a wear checking gauge line 24 or 25 on a male threadportion 18 and a female thread portion 19 of a go-side thread measuringportion 20 or a male thread portion 21 and a female thread portion 22 ofa not-go-side thread measuring portion 23 of the thread ring gauge bodyb or c by performing a marking process by sliding the positive electrodehandle on the male thread portion 18 and the female thread portion 19 ofthe go-side thread measuring portion 20 or the male thread portion 21and the female thread portion 22 of the not-go-side thread measuringportion 23 to form a concave shape which has a depth of 0.3 μm to 0.4 μmand a width of 0.2 mm and is blackened, or connecting a thread pluggauge body a to a negative electrode base connected to a power supplybox b which controls a current, setting a green stencil which has acut-out portion having a desired marking pattern and from which anelectrolytic solution exudes on a carbon filter with the electrolyticsolution being contained in a positive electrode handle connected to thepower supply box b, energizing the set positive electrode handle whilegripping the handle, and forming a wear checking round point on a malethread portion 7 and a female thread portion 8 of a go-side threadmeasuring portion 3 or a male thread portion 12 and a female threadportion 13 of a not-go-side thread measuring portion 5 of the threadplug gauge body a by performing a marking process without sliding thepositive electrode handle on the male thread portion 7 and the femalethread portion 8 of the go-side thread measuring portion 3 or the malethread portion 12 and the female thread portion 13 of the not-go-sidethread measuring portion 5 of the thread plug gauge body a to form aconcave shape which has a depth of 0.3 μm to 0.4 μm and a diameter of 2mm and is blackened.

Note that printing on a ceramic material is performed by a specialprinting method such as laser marking.

Effects of the Invention

The invention defined in claim 1 provides a thread plug gauge with amaintenance line or the like in which in a thread plug gauge body havinga go-side thread measuring portion extending from one side of a shankportion coaxially with the shank portion or a not-go-side threadmeasuring portion extending from the other side of the shank portioncoaxially with the shank portion,

a wear checking gauge line having a predetermined length and apredetermined depth or a round point having a predetermined depth and apredetermined diameter is formed on a male thread portion and a femalethread portion formed on the go-side thread measuring portion or thenot-go-side thread measuring portion. Accordingly, as the various typesof products are repeatedly threaded forward and backward into and fromthe go-side thread measuring portion or not-go-side thread measuringportion of the thread plug gauge, the wear checking gauge line wears outand disappears. Therefore, this invention has a merit of allowing theuser to visually check the limits of the thread gauge and reliably knowthe time for replacement of the plug gauge.

In addition, the present invention allows the user to properly replacethe thread plug gauge as the wear checking gauge line or the like wearsout and disappears as described above, and hence has a merit of beingcapable of producing a test object with high accuracy and preventing theproduction of defective products.

The invention defined in claim 2 provides a thread plug gauge with amaintenance line or the like in which the wear checking gauge lineformed on the male thread portion and the female thread portion of thego-side thread measuring portion or the not-go-side thread measuringportion has a linear shape. This invention therefore has the sameeffects as those of the invention defined in claim 1.

The invention defined in claim 3 provides a thread plug gauge with amaintenance line or the like in which the wear checking gauge line isprinted on the male thread portion and the female thread portion so asto have a depth of 0.3 μm to 0.4 μm and a width of 0.2 mm. Thisinvention therefore has the same effects as those of the inventiondefined in claim 1.

The invention defined in claim 4 provides a thread plug gauge with amaintenance line or the like in which the round point is printed on themale thread portion and the female thread portion so as to have a depthof 0.3 μm to 0.4 μm and a diameter of 2 mm. This invention therefore hasthe same effects as those of the invention defined in claim 1.

The invention defined in claim 5 provides a thread plug gauge with amaintenance line or the like in which the thread plug gauge with themaintenance line or the like is formed by using alloy tool steel, aceramic material, or a superhard material. This invention therefore hasthe same effects as those of the invention defined in claim 1.

The invention defined in claim 6 provides a method of manufacturing athread plug gauge with a maintenance line or the like, comprisingconnecting a thread plug gauge body to a negative electrode baseconnected to a power supply box which controls a current, setting agreen stencil which has a cut-out portion having a desired markingpattern and from which an electrolytic solution exudes on a carbonfilter with the electrolytic solution being contained in a positiveelectrode handle connected to the power supply box, energizing the setpositive electrode handle while gripping the handle, and forming a wearchecking gauge line on a male thread portion and a female thread portionof a go-side thread measuring portion or a male thread portion and afemale thread portion of a not-go-side thread measuring portion of thethread plug gauge body by performing a marking process by sliding thepositive electrode handle on the male thread portion and the femalethread portion of the go-side thread measuring portion or the malethread portion and the female thread portion of the not-go-side threadmeasuring portion of the thread plug gauge body to form a concave shapewhich has a depth of 0.3 μm to 0.4 μm and a width of 0.2 mm and isblackened, or connecting a thread plug gauge body to a negativeelectrode base connected to a power supply box which controls a current,setting a green stencil which has a cut-out portion having a desiredmarking pattern and from which an electrolytic solution exudes on acarbon filter with the electrolytic solution being contained in apositive electrode handle connected to the power supply box, energizingthe set positive electrode handle while gripping the handle, and forminga wear checking round point on a male thread portion and a female threadportion of a go-side thread measuring portion or a male thread portionand a female thread portion of a not-go-side thread measuring portion ofthe thread plug gauge body by performing a marking process withoutsliding the positive electrode handle on the male thread portion and thefemale thread portion of the go-side thread measuring portion or themale thread portion and the female thread portion of the not-go-sidethread measuring portion of the thread plug gauge body to form a concaveshape which has a depth of 0.3 μm to 0.4 μm and a diameter of 2 mm andis blackened. This invention has a merit of being capable of veryreliably and quickly producing a wear checking gauge line which canreliably inform the time for replacement of the thread plug gauge havingthe same effects as those of the invention defined in claim 1.

The invention defined in claim 7 provides a thread ring gauge with amaintenance line or the like in which in a thread ring gauge body havingan upper surface portion and a lower surface portion and having ago-side thread measuring portion formed on an inside portion to have amale thread portion and a female thread portion of the same class asthat of a screw to be measured or having a not-go-side thread measuringportion formed on an inside portion to have a male thread portion and afemale thread portion of the same class as that of a screw to bemeasured, wear checking gauge lines each having a predetermined lengthand a predetermined depth or round points each having a predetermineddepth and a predetermined diameter are formed on male thread portionsand female thread portions of the go-side thread measuring portion andthe not-go-side thread measuring portion which are engraved in an insideportion between the upper surface portion and the lower surface portionwhich constitute one of the thread ring gauge bodies. Accordingly, thisinvention therefore has a merit of allowing the user to visually checkthe limits of the thread gauge by letting the wear checking gauge linewear out and disappear and to reliably know the time for replacement ofthe thread ring gauge.

In addition, the present invention allows the user to properly replacethe thread ring gauge as the wear checking gauge line wears out asdescribed above, and hence has a merit of being capable of producing atest object with high accuracy and preventing the production ofdefective products.

The invention defined in claim 8 provides a thread ring gauge with amaintenance line or the like in which the wear checking gauge linedefined in claim 7 has a linear shape. This invention therefore has thesame effects as those of the invention defined in claim 7.

The invention defined in claim 9 provides a thread ring gauge with amaintenance line or the like in which the wear checking gauge linedefined in claim 7 is printed on the male thread portion and the femalethread portion so as to have a depth of 0.3 μm to 0.4 μm and a width of0.2 mm. This invention therefore has the same effects as those of theinvention defined in claim 7.

The invention defined in claim 10 provides a thread plug gauge with amaintenance line or the like in which the round point defined in claim 6is printed on the male thread portion and the female thread portion soas to have a depth of 0.3 μm to 0.4 μm and a diameter of 2 mm. Thisinvention therefore has the same effects as those of the inventiondefined in claim 6.

The invention defined in claim 11 provides a thread ring gauge with amaintenance line or the like in which the thread ring gauge body isformed by using alloy tool steel, a ceramic material, or a superhardmaterial. This invention therefore has the same effects as those of theinvention defined in claim

The invention defined in claim 12 provides a method of manufacturing athread ring gauge with a maintenance line or the like, characterized bycomprising connecting a thread ring gauge body to a negative electrodebase connected to a power supply box which controls a current, setting agreen stencil which has a cut-out portion having a desired markingpattern and from which an electrolytic solution exudes on a carbonfilter with the electrolytic solution being contained in a positiveelectrode handle connected to the power supply box, energizing the setpositive electrode handle while gripping the handle, and forming a wearchecking gauge line on a male thread portion and a female thread portionof a go-side thread measuring portion or a male thread portion and afemale thread portion of a not-go-side thread measuring portion of thethread ring gauge body by performing a marking process by sliding thepositive electrode handle on the male thread portion and the femalethread portion of the go-side thread measuring portion or the malethread portion and the female thread portion of the not-go-side threadmeasuring portion to form a concave shape which has a depth of 0.3 μm to0.4 μm and a width of 0.2 mm and is blackened, or connecting a threadring gauge body to a negative electrode base connected to a power supplybox which controls a current, setting a green stencil which has acut-out portion having a desired marking pattern and from which anelectrolytic solution exudes on a carbon filter with the electrolyticsolution being contained in a positive electrode handle connected to thepower supply box, energizing the set positive electrode handle whilegripping the handle, and forming a wear checking round point on a malethread portion and a female thread portion of a go-side thread measuringportion or a male thread portion and a female thread portion of anot-go-side thread measuring portion of the thread ring gauge body byperforming a marking process without sliding the positive electrodehandle on the male thread portion and the female thread portion of thego-side thread measuring portion or the male thread portion and thefemale thread portion of the not-go-side thread measuring portion of thethread ring gauge body to form a concave shape which has a depth of 0.3μm to 0.4 μm and a diameter of 2 mm and is blackened. This invention hasa merit of being capable of very reliably and quickly producing a wearchecking gauge line or the like which can reliably inform the time forreplacement of the thread ring gauge having the same effects as those ofthe invention defined in claim 7.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a thread plug gauge body with a maintenanceline or the like of a limit thread gauge according to the presentinvention.

FIG. 2 is a partially cutaway enlarged perspective view of the go-sidethread measuring portion of the plug gauge in FIG. 1.

FIG. 3 is a partially cutaway enlarged perspective view of thenot-go-side thread measuring portion of the thread plug gauge in FIG. 1.

FIG. 4 is a perspective view of the go-side thread measuring portion ofthe thread plug gauge in FIG. 1 before inspection.

FIG. 5 is a perspective view showing a state of the go-side threadmeasuring portion of the thread plug gauge in FIG. 4 at the time ofinspection.

FIG. 6 is a perspective view showing a state at the completion ofinspection in FIG. 5.

FIG. 7 is a perspective view showing a state of the not-go-side threadmeasuring portion of the thread plug gauge in FIG. 1 immediately beforethe measuring portion is threaded into a test object.

FIG. 8 is a perspective view showing a state immediately beforeinspection relative to the state in FIG. 7.

FIG. 9 is a perspective view showing a state when inspection starts fromthe state in FIG. 8.

FIG. 10 is a perspective view of the go-side thread measuring portion ofa thread ring gauge set with a maintenance line or the like according tothe present invention.

FIG. 11 is a perspective view of the not-go-side thread measuringportion of a thread ring gauge set with a maintenance line or the likeaccording to the present invention.

FIG. 12 is a front view of a go-side thread measuring portion in FIG.10.

FIG. 13 is a front view of a not-go-side thread measuring portion inFIG. 11.

FIG. 14 is a longitudinal front sectional view of the go-side threadmeasuring portion in FIG. 10.

FIG. 15 is a perspective view showing a state of the go-side threadmeasuring portion shown in FIG. 10 immediately before the measuringportion is threaded into a test object.

FIG. 16 is a perspective view showing an inspection state in which themeasuring portion in the state in FIG. 15 is threaded into the testobject.

FIG. 17 is a perspective view showing a state when the state in FIG. 16is viewed from the opposite side.

FIG. 18 is a perspective view showing a state of the not-go-side threadmeasuring portion of the thread ring gauge set with the maintenance lineor the like in FIG. 11 immediately before the measuring portion isthreaded into a test object.

FIG. 19 is a perspective view showing a state in which the not-go-sidethread measuring portion in FIG. 18 is threaded into the test object.

FIG. 20 is a perspective view showing a state when the state in FIG. 19in which the measuring portion is threaded into the test object isviewed from the opposite side.

FIG. 21 is a perspective view showing a state immediately before theformation a gauge line on the go-side thread measuring portion of thethread plug set shown in FIG. 1.

FIG. 22 is a perspective view showing a state in which a positiveelectrode handle in FIG. 21 is brought into contact with an end portionof the go-side thread measuring portion.

FIG. 23 is a perspective view showing a state in which the positiveelectrode handle in the state shown in FIG. 21 is slightly slid in thedirection of a shank portion.

FIG. 24 is a perspective view showing a state in which the positiveelectrode handle in the state in FIG. 23 is slid in the direction of theshank portion.

FIG. 25 is a perspective view of the go-side thread measuring portion onwhich a wear checking gauge line is printed in the process from thestate in FIG. 21 to the state in FIG. 24.

BEST MODE FOR CARRYING OUT THE INVENTION

The modes for carrying out the inventions defined in claims 1 to 12 arecommon, and hence will be collectively described below.

Referring to the accompanying drawings, reference symbol a denotes thethread plug gauge body of a thread plug gauge having a set of a go-sidethread measuring portion and a not-go-side thread measuring portioncoaxially extending from the left and right two sides of the shankportion of the thread gauge referred to as the thread gauge. The threadplug gauge body has the following arrangement.

The thread plug gauge body a has a prismatic shank portion 1 in themiddle portion. A left constricted portion 2 extends from the left sideof the shank portion 1. A go-side thread measuring portion 3 extendsfrom the left side of the constricted portion 2.

A right constricted portion 4 extends from the right side of the shankportion 1. A not-go-side thread measuring portion 5 extends from theright side of the right constricted portion 4.

The shank portion 1, the left and right two constricted portions 2 and4, the go-side thread measuring portion 3, and the not-go-side threadmeasuring portion 5 are coaxially formed.

As shown in FIG. 1, the present invention forms the go-side threadmeasuring portion 3 and the not-go-side thread measuring portion 5 as aset on the left and right two sides of the shank portion 1, and uses theresultant structure as a limit thread plug set. However, the go-sidethread measuring portion 3 or the not-go-side thread measuring portion 5may coaxially extend from one side of the shank portion 1, as describedabove.

The shank portion 1 generally has a hexagonal prismatic shape but is notlimited to it.

There are many types of thread gauges, other than those shown in theaccompanying drawings, which allow wear checking gauge lines to beprinted on the male and female thread portions of thread measuringportions, which the spirit of the present invention includes. Forexample, such gauges include, when a test object is a female screw, agauge having a go-side thread measuring portion formed on one side ofthe shank portion 1, a gauge having a not-go-side thread measuringportion formed on one side of the shank portion 1, a gauge having aninspection not-go-side thread measuring portion formed on one side ofthe shank portion 1, and a gauge having a working not-go-side threadmeasuring portion or the like formed on one side of the shank portion 1.When a test object is a male screw, such gauges include a go-side threadring gauge, not-go-side thread ring gauge, inspection not-go-side threadring gauge, and working not-go-side thread ring gauge. When a testobject to be inspected is a thread plug gauge, such gauges include ago-side wear checking thread ring gauge, not-go-side wear checkingthread ring gauge, go-side wear checking thread ring gauge, inspectionnot-go-side wear checking thread ring gauge, and working not-go-sidesear checking ring gauge. When a target object to be inspected is athread ring gauge, such gauges include a go-side wear checking threadring gauge, inspection not-go-side wear checking thread plug gauge, andworking not-go-side wear checking thread plug gauge.

As shown in the accompanying drawings, the go-side thread measuringportion 3 has a thread having a predetermined length helically engravedsuch that male thread portions (thread crests) 7 and female threadportions (thread roots) 8 are alternately formed.

Referring to the accompanying drawings, reference numeral 9 denotes awear checking gauge line having a depth of 0.3 μm to 0.4 μm and a widthof 0.2 mm, which is formed by printing processing on the male threadportions 7 and the female thread portions 8 between an end portion 6 ofthe go-side thread measuring portion 3 and the left constricted portion2. Although the length of the wear checking gauge line 9 generallycovers all the male thread portions 7 and the female thread portions 8between the end portion 6 of the go-side thread measuring portion 3 andthe left constricted portion 2, printing processing may be applied tosome of the male thread portions 7 and the female thread portions 8.

The wear checking gauge line 9 is generally linear but is not limited tothis.

In the present invention, a wear checking gauge line which is identicalto the wear checking gauge line 9 and has a depth of 0.3 μm to 0.4 μmand a width of 0.2 mm is formed on male thread portions (thread crests)12 and female thread portions (thread roots) 13 formed between an endportion 10 of the not-goside thread measuring portion 5 and the rightconstricted portion 4 by printing processing.

Although the length of the wear checking gauge line 14 generally coversall the male thread portions 12 and the female thread portions 13between the end portion 10 of the not-go-side thread measuring portion 5and the right constricted portion 4, printing processing may be appliedto some of the male thread portions 12 and female thread portions 13.

The wear checking gauge line 14 is generally linear but is not limitedto this.

The prismatic shank portion 1, the left and right two constrictedportions 2 and 4, the go-side thread measuring portion 3, and thenot-go-side thread measuring portion 5 are coaxially formed.

The thread plug gauge with the maintenance line or the like, which isconstituted by the prismatic shank portion 1, the two constrictedportions 2 and 4, the go-side thread measuring portion 3, and thenot-go-side thread measuring portion 5, is formed by using alloy toolsteel, a ceramic material, a superhard material, or the like.

The following will describe a printing processing method according tothe spirit of the present invention, which is performed to print thewear checking gauge lines 9 and 14 on the male thread portions 7 and 12and the female thread portions 8 and 13 forming the go-side threadmeasuring portion 3 and not-go-side thread measuring portion 5 of thethread plug gauge body a.

That is, this method uses a power supply box d which controls a current.

A negative electrode base is connected to the power supply box d.

A positive electrode handle is further connected to the power supply boxd.

The thread plug gauge body a is connected to the negative electrodebase.

A green stencil which has a cut-out portion having a desired markingpattern and from which an electrolytic solution exudes is then set on acarbon filter with the electrolytic solution being contained in apositive electrode handle connected to the power supply box d.

Note that printing on a ceramic material is performed by a specialprinting method such as laser marking.

While the user grips the positive electrode handle set in the abovemanner, the handle is energized and slid on the surfaces of the malethread portions 7 and female thread portions 8 of the go-side threadmeasuring portion 3 of the thread plug gauge body a and the surfaces ofthe male thread portions 12 and female thread portions 13 of thenot-go-side thread measuring portion 5.

As described above, the positive electrode handle is applied to thego-side thread measuring portion 3 such that the positive electrodehandle is kept still in contact with the surfaces of each male threadportion 7 and each female thread portion 8 for about 2 sec and slid froma side of the end portion 6, on which neither male thread portions 7 norfemale thread portions 8 are formed, in the direction of the constrictedportion 2.

As a result, a marking process is performed to form the above wearchecking gauge line on the surfaces of the male thread portions 7 andfemale thread portions 8 by forming a concave shape which has a depth of0.3 μm to 0.4 μm and a width of 0.2 mm and is blackened.

In addition, the wear checking gauge line 14 is formed on the surfacesof the male thread portions 12 and female thread portions 13 of thenot-go-side thread measuring portion 5 on the not-go side of the threadplug gauge body a by a technique similar to the above marking processstep of forming the wear checking gauge line 9 on the surfaces of themale thread portions 7 and female thread portions 8 of the go-sidethread measuring portion 3.

However, a slight difference between these techniques is that thepositive electrode handle connected to the power supply box d is keptstill in contact with the surfaces of each male thread portion 12 andeach female thread portion 13 for about 2 sec and slid from the endportion 10 of the not-go-side thread measuring portion 5 in thedirection of the right constricted portion 4.

The above description is about the printing process step for the wearchecking gauge line of the thread gauge with the maintenance line or thelike according to the present invention.

Reference symbol b denotes a thread ring set body which measures the goside of a thread product 26 and has the following arrangement.

The thread ring set body b has an upper surface portion 15 and a lowersurface portion 16. The thread ring set body b also has, on an insideportion 17, a go-side thread measuring portion 20 having male threadportions 18 and female thread portions 19 of the same class as that of ascrew to be measured.

Reference symbol c denotes a thread ring set body which measures thenot-go side of a thread product 27 and has the following arrangement.

The thread ring set body c has an upper surface portion 15 and a lowersurface portion 16 and also has a not-go-side thread measuring portion23 having, on an inside portion 17, male thread portions 21 and femalethread portions 22 of the same class as that of a screw to be measured.

Reference numeral 24 denotes a wear checking gauge line which isprovided on the go-side thread measuring portion 20 described above andhas the following arrangement.

That is, the gauge line 24 having a depth of 0.3 μm to 0.4 μm and awidth of 0.2 mm is formed by printing on the male thread portions 18 andfemale thread portions 19 of the go-side thread measuring portion 20which are engraved between the upper surface portion 15 and the lowersurface portion 16 which constitute the thread ring set body b. Thegauge line 24 is generally linear but is not limited to this.

Note that printing on a ceramic material is performed by a specialprinting method such as laser marking.

Reference numeral 25 denotes a wear checking gauge line which isprovided on the not-go-side thread measuring portion 23 described aboveand has the following arrangement.

That is, the gauge line 25 having a depth of 0.3 μm to 0.4 μm and awidth of 0.2 mm is formed by printing on the male thread portions 21 andfemale thread portions 22 of the not-go-side thread measuring portion 23which are engraved between the upper surface portion 15 and the lowersurface portion 16 which constitute the thread ring set body c. Thegauge line 25 is generally linear but is not limited to this.

The limit thread ring gauge bodies b and c are formed by using alloytool steel, a ceramic material, or a superhard material.

The following will describe a method of manufacturing the wear checkinggauge line 24 or 25 on the male thread portions 18 and female threadportions 19 of the go-side thread measuring portion 20 of the threadring gauge body b or the male thread portions 21 and female threadportions 22 of the not-go-side thread measuring portion 23 of the threadring gauge body c.

In order to form the wear checking gauge line 24 or 25 on the malethread portions 18 and female thread portions 19 of the go-side threadmeasuring portion 20 of the thread ring gauge body b or the male threadportions 21 and female thread portions 22 of the not-go-side threadmeasuring portion 23 of the thread ring gauge body c, first of all, thethread ring gauge body b or c is connected to the negative electrodebase connected to the power supply box d which controls a current, and agreen stencil which has a cut-out portion having a desired markingpattern and from which an electrolytic solution exudes is then set on acarbon filter with the electrolytic solution being contained in apositive electrode handle connected to the power supply box d. While theuser grips the positive electrode handle set in the above manner, thehandle is energized and slid on the male thread portions 18 and femalethread portions 19 of the go-side thread measuring portion 20 or themale thread portions 21 and female thread portions 22 of the not-go-sidethread measuring portion 23. As a result, a marking process is performedto form the wear checking gauge line 24 or 25 on the surface portions ofone set of the male thread portions 18 and female thread portions 19 orthe other set of the male thread portions 21 and female thread portions22 by forming a concave shape which has a depth of 0.3 μm to 0.4 μm anda width of 0.2 mm and is blackened.

The above description is about the printing process step for the wearchecking gauge line of the thread ring set body b or c with themaintenance line or the like according to the present invention.

The usage of the thread gauge with the maintenance line or the likeaccording to the present invention will be further described below.

The usage of the thread plug set body a will be described first.

The go-side thread measuring portion 3 forming the thread plug gaugebody a is threaded into a female thread 27 of the test object 26stepwise from FIG. 4 to FIG. 5 and from FIG. 5 to FIG. 6, and is thenthreaded backward.

As gauge measurement is continuously repeated between the go-side threadmeasuring portion 3 and the test object 26 in the process shown in theabove drawings and the female thread 27 of the test object 26 makesfrequent contact with the male thread portions 7 and female threadportions 8 of the go-side thread measuring portion 3, the wear checkinggauge line 9 formed on the male thread portions 7 and female threadportions 8 of the go-side thread measuring portion 3 graduallydisappears due to the contact.

As the wear checking gauge line 9 disappears through a gauge processlike that described above, the user can reliably check and know thepredetermined upper and lower limits of dimensional accuracy of a threadproduct. This makes it possible to reliably know the time forreplacement of the thread gauge.

The usage of the not-go-side thread measuring portion 5 of the threadplug gauge body a is to repeatedly thread forward and backward thenot-go-side thread measuring portion 5 into and from the female thread27 of the test object 26 by the same method as the conventional gaugemethod, as shown in FIGS. 7, 8, and 9.

As gauge measurement is repeated between the test object 26 and thenot-go-side thread measuring portion 5 and the female thread 27 of thetest object 26 makes frequent contact with the male thread portions 12and female thread portions 13 of the not-go-side thread measuringportion 5, the wear checking gauge line 14 formed on the male threadportions 12 and female thread portions 13 of the not-go-side threadmeasuring portion 5 gradually disappears due to the contact.

As the wear checking gauge line 14 disappears through a gauge processlike that described above, the user can reliably check and know thepredetermined upper and lower limits of dimensional accuracy of a threadproduct. This makes it possible to reliably know the time forreplacement of the thread gauge.

The usage of the thread ring set body b of the ring gauge with themaintenance line or the like according to the present invention will bedescribed below.

The usage of the ring gauge body b is to repeatedly thread forward andbackward male thread 28 of the test object 26 into and from the go-sidethread measuring portion 20 of the thread ring set body b, as shown inFIGS. 15, 16, and 17.

For this reason, as the male thread 28 of the test object 26 makesfrequent contact with the male thread portions 18 and female threadportions 19 of the go-side thread measuring portion 20, the wearchecking gauge line 24 formed on the male thread portions 18 and femalethread portions 19 of the go-side thread measuring portion 20 of thethread ring gauge body b gradually disappears due to the contact.

When the wear checking gauge line 24 disappears as described above, theuser can reliably check and know the predetermined upper and lowerlimits of dimensional accuracy of a thread product. This makes itpossible to reliably know the time for replacement of the thread gauge.

The usage of the thread ring set body c of the thread gauge with themaintenance line or the like according to the present invention will bedescribed below.

The usage of the ring gauge body c is to repeatedly thread forward andbackward male thread 29 of a test object 28 into and from thenot-go-side thread measuring portion 23 of the thread ring gauge body c,as shown in FIGS. 18, 19, and 20.

For this reason, the male thread 29 of the test object 28 makes frequentcontact with the male thread portions 21 and female thread portions 22of the not-go-side thread measuring portion 23. As a consequence, thewear checking gauge line 25 formed on the male thread portions 21 andfemale thread portions 22 of the not-go-side thread measuring portion 23of the thread ring gauge body c gradually disappears due to the contact.

When the wear checking gauge line 25 disappears as described above, theuser can reliably check and know the predetermined upper and lowerlimits of dimensional accuracy of a thread product. This makes itpossible to reliably know the time for replacement of the thread gauge.

The round point is not shown in the accompanying drawings, as it isdetermined that the textual explanation suffices.

REFERENCE SIGNS LIST

-   -   a thread plug gauge body    -   b thread ring gauge body    -   c thread ring gauge body    -   d power supply box    -   1 shank portion    -   2 constricted portion    -   3 thread measuring portion    -   4 constricted portion    -   5 not-go-side thread measuring portion    -   6 end portion    -   7 male thread portion    -   8 female thread portion    -   9 wear checking gauge line    -   10 end portion    -   12 male thread portion    -   13 female thread portion    -   14 wear checking gauge line    -   15 upper surface portion    -   16 lower surface portion    -   17 inside portion    -   18 male thread portion    -   19 female thread portion    -   20 go-side thread measuring portion    -   21 male thread portion    -   22 female thread portion    -   23 not-go-side thread measuring portion    -   24 wear checking gauge line    -   25 wear checking gauge line    -   26 test object    -   27 female thread    -   28 male thread    -   29 male thread portion

What is claimed is:
 1. A thread plug gauge with a maintenance line, thethread plug gauge comprising: a thread plug gauge body having a go-sidethread measuring portion extending from one side of a shank portioncoaxially with the shank portion or a not-go-side thread measuringportion extending from an other side of the shank portion coaxially withthe shank portion; a wear checking gauge line having a predeterminedlength and a predetermined depth or a round point having a predetermineddepth and a predetermined diameter formed on a male thread portion and afemale thread portion formed on the go-side thread measuring portion orthe not-go-side thread measuring portion.
 2. The thread plug gauge withthe maintenance line according to claim 1, wherein the wear checkinggauge line formed on the male thread portion and the female threadportion of the go-side thread measuring portion or the not-go-sidethread measuring portion has a linear shape.
 3. The thread plug gaugewith the maintenance line according to claim 2, wherein the wearchecking gauge line is printed on the male thread portion and the femalethread portion so as to have a depth of 0.3 μm to 0.4 μm and a width of0.2 mm.
 4. The thread plug gauge with the maintenance line according toclaim 3, wherein the thread plug gauge with the maintenance line isformed by using alloy tool steel, a ceramic material, or a superhardmaterial.
 5. The thread plug gauge with the maintenance line accordingto claim 2, wherein the thread plug gauge with the maintenance line isformed by using alloy tool steel, a ceramic material, or a superhardmaterial.
 6. The thread plug gauge with the maintenance line accordingto claim 1, wherein the wear checking gauge line is printed on the malethread portion and the female thread portion so as to have a depth of0.3 μm to 0.4 μm and a width of 0.2 mm.
 7. The thread plug gauge withthe maintenance line according to claim 6, wherein the thread plug gaugewith the maintenance line is formed by using alloy tool steel, a ceramicmaterial, or a superhard material.
 8. The thread plug gauge with themaintenance line according to claim 1, wherein the round point isprinted on the male thread portion and the female thread portion so asto have a depth of 0.3 μm to 0.4 μm and a diameter of 2 mm.
 9. Thethread plug gauge with the maintenance line according to claim 8,wherein the thread plug gauge with the maintenance line is formed byusing alloy tool steel, a ceramic material, or a superhard material. 10.The thread plug gauge with the maintenance line according to claim 1,wherein the thread plug gauge with the maintenance line is formed byusing alloy tool steel, a ceramic material, or a superhard material.